WATTPAD SUGGESTIONS? :)

What are the domain and range of the function? f(x) = -4 (sqrt)x

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is

Ineed to know the answer right now! !